It has been known in the past to attempt to accommodate the expansion of shield members and the surrounding encapsulating casting resin during the curing process for the casting of terminal-bushings, or like casting products. For example, reference may be made to U.S. Pat. No. 3,001,004, issued Sept. 19, 1961 to Richard G. Black. In this patent a slotted metallic shell is provided as a shell for forming a part of the resultant terminal-bushing. Also reference may be had to U.S. Pat. No. 3,001,005, issued Sept. 19, 1961 to Charles F. Sonnenberg, in which a cylinderical metallic screening may be embedded in the resin body 13 of a terminal-bushing. Casting materials are set forth for example in U.S. Pat. Nos. 2,997,526 - Kessel et al; 2,997,527 Kessel et al; and 2,997,528 - Kessel et al.
In U.S. Pat. No. 3,146,518, issued Sept. 1, 1964 to Mitsuhiro Kishida, a sprayed conducting layer of metal may be provided over sections in the successive building up to a suitable terminal-bushing. In U.S. Pat. No. 3,222,625, issued Dec. 7, 1967 to Marcel Ledocq screening is provided in a resinous-type terminal-bushing. Also a screening element is used in U.S. Pat. No. 3,230,301, issued Jan. 18, 1966 to Charles F. Sonnenberg and Donald J. Martahus.
In U.S. Pat. No. 3,265,799, issued Aug. 9, 1966 to James H. McWhirter, screening is used in centrifugally-formed sectional layers of a terminal-bushing.